Search results for: structural safety.

Authors: P. O. Angienda, D. J. Hill

Abstract:

The purpose of this study was to elucidate the factors affecting antimicrobial effectiveness of essential oils against food spoilage and pathogenic bacteria. The minimum inhibition concentrations (MIC) of the essential oils, were determined by turbidimetric technique using Biocreen C, analyzer. The effects of pH ranging from 7.3 to 5.5 in absence and presence of essential oils and/or NaCl on the lag time and mean generation time of the bacteria at 370C, were carried out and results were determined showed that, combination of low pH and essential oil at 370C had additive effects against the test micro-organisms. The combination of 1.2 % (w/v) of NaCl and clove essential oil at 0.0325% (v/v) was effective against E. coli. The use of concentrations less than MIC in combination with low pH and or NaCl has the potential of being used as an alternative to “traditional food preservatives".

Keywords: Antimicrobial, Bacteria, Bioscreen C, essential oil.

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Authors: Yongxin Yuan, Jiashang Jiang

Abstract:

A new numerical method for simultaneously updating mass and stiffness matrices based on incomplete modal measured data is presented. By using the Kronecker product, all the variables that are to be modified can be found out and then can be updated directly. The optimal approximation mass matrix and stiffness matrix which satisfy the required eigenvalue equation and orthogonality condition are found under the Frobenius norm sense. The physical configuration of the analytical model is preserved and the updated model will exactly reproduce the modal measured data. The numerical example seems to indicate that the method is quite accurate and efficient.

Keywords: Finite element model, model updating, modal data, optimal approximation.

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Authors: Ilze Stokmane

Abstract:

Baltic competitiveness is quite controversial. In a situation with the rapid structural changes, economy develops in balance very rarely - in different fields will always be more rapid changes in another more stagnation. Analyzing different economic indices developed by international organizations the situation in three Baltic countries are described from a different competitiveness positions highlighting strengths and weaknesses of each country. Exploring the openness of the economy, it is possible to observe certain risks included in the reports describing situation of competitiveness where government policies competing in the tax system, the rates of labour market policies, investment environment, etc. This is a very important factor resulting in competitive advantage. Baltic countries are still at a weak position from a technological perspective, and need to borrow the knowledge and technology from more developed countries.

Keywords: Baltic countries, Baltic region, competitiveness, indices of competitiveness.

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Authors: Shivayogi Charantimath

Abstract:

Radiotherapy and chemotherapy are effective for treating malignancies but are associated with side effects like oral mucositis. Chlorhexidine gluconate is one of the most commonly used mouthwash in prevention of signs and symptoms of mucositis. Evidence shows that chlorhexidine gluconate has side effects in terms of colonization of bacteria, bad breadth and less healing properties. Thus, it is essential to find a suitable alternative therapy which is more effective with minimal side effects. Curcumin, an extract of turmeric is gradually being studied for its wide-ranging therapeutic properties such as antioxidant, analgesic, anti-inflammatory, antitumor, antimicrobial, antiseptic, chemo sensitizing and radio sensitizing properties. The present study was conducted to evaluate the efficacy and safety of topical curcumin gel on radio-chemotherapy induced oral mucositis in cancer patients. The aim of the study is to evaluate the efficacy and safety of curcumin gel in the management of oral mucositis in cancer patients undergoing radio chemotherapy and compare with chlorhexidine. The study was conducted in K.L.E. Society’s Belgaum cancer hospital. 40 oral cancer patients undergoing the radiochemotheraphy with oral mucositis was selected and randomly divided into two groups of 20 each. The study group A [20 patients] was advised Cure next gel for 2 weeks. The control group B [20 patients] was advised chlorhexidine gel for 2 weeks. The NRS, Oral Mucositis Assessment scale and WHO mucositis scale were used to determine the grading. The results obtained were calculated by using SPSS 20 software. The comparison of grading was done by applying Mann-Whitney U test and intergroup comparison was calculated by Wilcoxon matched pairs test. The NRS scores observed from baseline to 1^st and 2^nd week follow up in both the group showed significant difference. The percentage of change in erythema in respect to group A was 63.3% for first week and for second week, changes were 100.0% with p = 0.0003. The changes in Group A in respect to erythema was 34.6% for 1^st week and 57.7% in second week. The intergroup comparison was significant with p value of 0.0048 and 0.0006 in relation to group A and group B respectively. The size of the ulcer score was measured which showed 35.5% [P=0.0010] of change in Group A for 1^st and 2^nd week showed totally reduction i.e. 103.4% [P=0.0001]. Group B showed 24.7% change from baseline to 1^st week and 53.6% for 2^nd week follow up. The intergroup comparison with Wilcoxon matched pair test was significant with p=0.0001 in group A. The result obtained by WHO mucositis score in respect to group A shows 29.6% [p=0.0004] change in first week and 75.0% [p=0.0180] change in second week which is highly significant in comparison to group B. Group B showed minimum changes i.e. 20.1% in 1^st week and 33.3% in 2^nd week. The p value with Wilcoxon was significant with 0.0025 in Group A for 1^st week follow up and 0.000 for 2^nd week follow up. Curcumin gel appears to an effective and safer alternative to chlorhexidine gel in treatment of oral mucositis.

Keywords: Curcumin, chemotherapy, mucositis, radiotherapy.

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Authors: Kee-Young Kwahk

Abstract:

Cognizant of the fact that enterprise systems involve organizational change and their implementation is over shadowed by a high failure rate, it is argued that there is the need to focus attention on employees- perceptions of such organizational change when explaining adoption behavior of enterprise systems. For this purpose, the research incorporates a conceptual constructo fattitude toward change that captures views about the need for organizational change. Centered on this conceptual construct, the research model includes beliefs regarding the system and behavioral intention as its consequences, and the personal characteristics of organizational commitment and perceived personal competence as its antecedents. Structural equation analysis using LISREL provides significant support for the proposed relationships. Theoretical and practical implications are discussed along with limitations.

Keywords: Sociotechnical changes, organizational change, attitude toward change, enterprise information systems.

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Authors: A. Darvizeh, H. Rajabi, S. Fatahtooei Nejad, A. Khaheshi, P. Haghdoust

Abstract:

In this article, biomechanical aspects of hen-s eggshell as a natural ceramic structure are studied. The images, taken by a scanning electron microscope (SEM), are used to investigate the microscopic aspects of the egg. It is observed that eggshell has a three-layered microstructure with different morphological and structural characteristics. Studies on the eggshell membrane (ESM) as a prosperous tissue suggest that it is placed to prevent the penetration of microorganisms into the egg. Finally, numerical models of the egg are presented to study the stress distribution and its deformation under different loading conditions. The effects of two different types of loading (hydrostatic and point loadings) on two different shell models (with constant and variable thicknesses) are investigated in detail.

Keywords: Eggshell, biomechanical properties, Scanning electron microscope, Numerical Modeling.

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Authors: Shimal Das, Dibyendu Ghoshal

Abstract:

The effect of directional search using iterated functional system has been studied on four images taken from databases. The images are portioned successively towards smaller dimension. Presented method provides the faster rate of convergence with respect to processing time in the flat region, but the same has been found to be slower at the border of the images and edges. It has also been revealed that the PSNR is lower at the edges and border portions of the image, and it is found to be higher in the uniform gray region, under the same external illumination and external noise environment.

Keywords: Iterated functional system, fractal compression, structural similarity index measure, fractal block coding, affine transformations.

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Authors: W. S. Hsu, S. W. Chen, Y. T. Ku, Y. Chiang, J. R. Wang , J. H. Yang, C. Shih

Abstract:

ALOHA code was used to calculate the concentration under the CO₂ storage burst condition for Maanshan nuclear power plant (NPP) in this study. Five main data are input into ALOHA code including location, building, chemical, atmospheric, and source data. The data from Final Safety Analysis Report (FSAR) and some reports were used in this study. The ALOHA results are compared with the failure criteria of R.G. 1.78 to confirm the habitability of control room. The result of comparison presents that the ALOHA result is below the R.G. 1.78 criteria. This implies that the habitability of control room can be maintained in this case. The sensitivity study for atmospheric parameters was performed in this study. The results show that the wind speed has the larger effect in the concentration calculation.

Keywords: PWR, ALOHA, habitability, Maanshan.

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Authors: S. Iffat, B. Bose

Abstract:

Concrete as a construction material is versatile because it displays high degree of fire-resistance. Concrete’s inherent ability to combat one of the most devastating disaster that a structure can endure in its lifetime, can be attributed to its constituent materials which make it inert and have relatively poor thermal conductivity. However, concrete structures must be designed for fire effects. Structural components should be able to withstand dead and live loads without undergoing collapse. The properties of high-strength concrete must be weighed against concerns about its fire resistance and susceptibility to spalling at elevated temperatures. In this paper, the causes, effects and some remedy of deterioration in concrete due to fire hazard will be discussed. Some cost effective solutions to produce a fire resistant concrete will be conversed through this paper.

Keywords: Concrete, fire, spalling, temperature, compressive strength, density.

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Authors: M. Kowalski, M. Kastek, M. Szustakowski

Abstract:

Multispectral screening systems are becoming more popular because of their very interesting properties and applications. One of the most significant applications of multispectral screening systems is prevention of terrorist attacks. There are many kinds of threats and many methods of detection. Visual detection of objects hidden under clothing of a person is one of the most challenging problems of threats detection. There are various solutions of the problem; however, the most effective utilize multispectral surveillance imagers. The development of imaging devices and exploration of new spectral bands is a chance to introduce new equipment for assuring public safety. We investigate the possibility of long lasting detection of potentially dangerous objects covered with various types of clothing. In the article we present the results of comparative studies of passive imaging in three spectrums – visible, infrared and terahertz.

Keywords: Infrared, image processing, object detection, screening camera, terahertz.

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Authors: Simon L. Madsen, Mads Dyrmann, Morten S. Laursen, Rasmus N. Jørgensen

Abstract:

Recent advances in the Unmanned Aerial System (UAS) safety and perception systems enable safe low altitude autonomous terrain following flights recently demonstrated by the consumer DJI Mavic PRO and Phamtom 4 Pro drones. This paper presents the first prototype system utilizing this functionality in form of semi-automated UAS based collection of crop/weed images where the embedded perception system ensures a significantly safer and faster gathering of weed images with sub-millimeter resolution. The system is to be used when the weeds are at cotyledon stage and prior to the harvest recognizing the grass weed species, which cannot be discriminated at the cotyledon stage.

Keywords: Weed mapping, integrated weed management, DJI SDK, automation, cotyledon plants.

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Authors: Lenka Ševelová, Aleš Florian

Abstract:

Appropriate and progressive tool for analyzing behavior of low volume roads are probabilistic models used in reliability analyses. The necessary part of the probabilistic model is the deterministic model of structural behavior. The FE model of low volume roads is created in the ANSYS software. It is able to determine the state of stress and deformation in any point of the structure and thus generate data required for the reliability analysis. The paper compares two material constitutive models used for modeling of unbound non-homogenous materials used in low volume roads. The first model is linear elastic model according to Hook theory (H model), the second one is nonlinear elastic-plastic Drucker-Prager model (D-P model).

Keywords: FEA, FEM, geotechnical materials, low volume roads, material constitutive models, pavement.

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Authors: Adel Smeda, Adel Alti, Mourad Oussalah, Abdallah Boukerram

Abstract:

A key aspect of the design of any software system is its architecture. An architecture description provides a formal model of the architecture in terms of components and connectors and how they are composed together. COSA (Component-Object based Software Structures), is based on object-oriented modeling and component-based modeling. The model improves the reusability by increasing extensibility, evolvability, and compositionality of the software systems. This paper presents the COSA modelling tool which help architects the possibility to verify the structural coherence of a given system and to validate its semantics with COSA approach.

Keywords: Software Architecture, Architecture Description Languages, UML, Components, Connectors.

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Authors: Eric Filiol

Abstract:

This paper presents a protocol aiming at proving that an encryption system contains structural weaknesses without disclosing any information on those weaknesses. A verifier can check in a polynomial time that a given property of the cipher system output has been effectively realized. This property has been chosen by the prover in such a way that it cannot been achieved by known attacks or exhaustive search but only if the prover indeed knows some undisclosed weaknesses that may effectively endanger the cryptosystem security. This protocol has been denoted zero-knowledge-like proof of cryptanalysis. In this paper, we apply this protocol to the Bluetooth core encryption algorithm E0, used in many mobile environments and thus we suggest that its security can seriously be put into question.

Keywords: Bluetooth encryption, Bluetooth security, Bluetoothprotocol, Stream cipher, Zero-knowledge, Cryptanalysis

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Authors: Azza M. Anis, M. M. Abutaleb, Hani F. Ragai, M. I. Eladawy

Abstract:

This paper presents the characterization and design of a capacitive pressure sensor with LC-based 0.35 µm CMOS readout circuit. SPICE is employed to evaluate the characteristics of the readout circuit and COMSOL multiphysics structural analysis is used to simulate the behavior of the pressure sensor. The readout circuit converts the capacitance variation of the pressure sensor into the frequency output. Simulation results show that the proposed pressure sensor has output frequency from 2.50 to 2.28 GHz in a pressure range from 0.1 to 2 MPa almost linearly. The sensitivity of the frequency shift with respect to the applied pressure load is 0.11 GHz/MPa.

Keywords: CMOS LC-based oscillator, micro pressure sensor, silicon carbide

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Authors: S. R. Shamili, J. Karthikeyan

Abstract:

Fast development of the total populace and far and wide urbanization has surprisingly expanded the advancement of the construction industry. As a result of these activities, old structures are being demolished to make new buildings. Due to these large-scale demolitions, a huge amount of debris is generated all over the world, which results in a landfill. The use of construction and demolition waste as landfill causes groundwater contamination, which is hazardous. Using construction and demolition waste as aggregate can reduce the use of natural aggregates and the problem of mining. The objective of this study is to provide a detailed overview on how the construction and demolition waste material has been used as aggregate in structural concrete. In this study, the preparation, classification, and composition of construction and demolition wastes are also discussed.

Keywords: Aggregate, construction and demolition waste, landfill, large scale demolition.

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Authors: S. S. Ngu, L. C. Kho, T. P. Tan, M. S. Osman

Abstract:

This work deals with the design of the robotic assembly system for the roller clamps. The task is characterized by high speed, high yield and safety engagement. This paper describes the design of different parts of an automated high speed machine to assemble the parts of roller clamps. The roller clamp robotic assembly system performs various processes in the assembly line which include clamp body and roller feeding, inserting the roller into the clamp body, and dividing the rejected clamp and successfully assembled clamp into their own tray. The electrical/electronics design of the machine is discussed. The target is to design a cost effective, minimum maintenance and high speed machine for the industry applications.

Keywords: Machine design, assembly machine, roller clamp, industry applications.

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Authors: Emiliano Matta

Abstract:

Passive resonant vibration absorbers are among the most widely used dynamic control systems in civil engineering. They typically consist in a single-degree-of-freedom mechanical appendage of the main structure, tuned to one structural target mode through frequency and damping optimization. One classical scheme is the pendulum absorber, whose mass is constrained to move along a curved trajectory and is damped by viscous dashpots. Even though the principle is well known, the search for improved arrangements is still under way. In recent years this investigation inspired a type of bidirectional pendulum absorber (BPA), consisting of a mass constrained to move along an optimal three-dimensional (3D) concave surface. For such a BPA, the surface principal curvatures are designed to ensure a bidirectional tuning of the absorber to both principal modes of the main structure, while damping is produced either by horizontal viscous dashpots or by vertical friction dashpots, connecting the BPA to the main structure. In this paper, a variant of BPA is proposed, where damping originates from the variable tangential friction force which develops between the pendulum mass and the 3D surface as a result of a spatially-varying friction coefficient pattern. Namely, a friction coefficient is proposed that varies along the pendulum surface in proportion to the modulus of the 3D surface gradient. With such an assumption, the dissipative model of the absorber can be proven to be nonlinear homogeneous in the small displacement domain. The resulting homogeneous BPA (HBPA) has a fundamental advantage over conventional friction-type absorbers, because its equivalent damping ratio results independent on the amplitude of oscillations, and therefore its optimal performance does not depend on the excitation level. On the other hand, the HBPA is more compact than viscously damped BPAs because it does not need the installation of dampers. This paper presents the analytical model of the HBPA and an optimal methodology for its design. Numerical simulations of single- and multi-story building structures under wind and earthquake loads are presented to compare the HBPA with classical viscously damped BPAs. It is shown that the HBPA is a promising alternative to existing BPA types and that homogeneous tangential friction is an effective means to realize systems provided with amplitude-independent damping.

Keywords: Amplitude-independent damping, Homogeneous friction, Pendulum nonlinear dynamics, Structural control, Vibration resonant absorbers.

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Authors: Titanilla Komenda, Viktorio Malisa

Abstract:

In this paper, the influence of diversity-related factors on the design of collaborative scenarios is analysed. Based on the evaluation, a framework for simulating human-robot-collaboration is presented that considers both human factors as well as the overall system performance. The implementation of the model is shown on a real-life scenario from industry and validated in terms of traceability, safety and physical limitations. By comparing scenarios that consider diversity with those only meeting system performance, an overall understanding of individually adapted human-robot-collaborative workspaces is reached. A diversity-related guideline for human-robot-collaborations provides a summary of the research and aids in optimizing future applications. Finally, limitations and future amendments of the model are discussed.

Keywords: Diversity, human-machine-system, human-robot-collaboration, simulation.

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Authors: Devdutt

Abstract:

In this paper, passenger seat vibration control of an active quarter car model under random road excitations is considered. The designed ANFIS and Summing ANFIS PID controllers are assembled in primary suspension system of quarter car model. Simulation work is performed in time and frequency domain to obtain passenger seat acceleration and displacement responses. Simulation results show that Summing ANFIS PID based controller is highly suitable to suppress the road induced vibrations in quarter car model to achieve desired passenger ride comfort and safety compared to ANFIS and passive system.

Keywords: Quarter car model, Active suspension system, Summing ANFIS PID controller, Passenger ride comfort.

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Authors: Sebastian B. Mendes

Abstract:

The presence of a vertical edge-crack within a web plate subjected to pure bending induces local compressive stresses about the crack which may cause tension buckling. Approximate theoretical expressions were derived for the critical far-field tensile stress and bending moment capacity of an edge-cracked web plate associated with tension buckling. These expressions were validated with finite element analyses and used to investigate the possibility of tension buckling in web-cracked trial girders. It was found that tension buckling is an unlikely occurrence unless the web is relatively thin or the crack is very long.

Keywords: Fatigue crack, tension buckling, Rayleigh-Ritz, structural stability.

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Authors: Yolanda Ramírez, Ángel Tejada, Agustín Baidez

Abstract:

The purpose of this paper is to examine the quality of voluntary intellectual capital disclosure by public Spanish universities on their websites. To this end, a content analysis was used to analyze the websites of 50 public Spanish universities i 2016. The results of this study show that human capital was the most disclosed category with relational capital being the least frequently disclosed in Spain. However, the quality of structural capital disclosures was higher than relational and human capital. Finally, most IC disclosures were narrative in nature.

Keywords: Intellectual capital, quality disclosure, websites, universities, Spain.

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Authors: Trevor N. Haas, Alexander Koen

Abstract:

Columns have traditionally been constructed of reinforced concrete or structural steel. Much attention was allocated to estimate the axial capacity of the traditional column sections to the detriment of other forms of construction. Other forms of column construction such as Concrete Filled Double Skin Tubes received little research attention, and almost no attention when subjected to eccentric loading. This paper investigates the axial capacity of columns when subjected to eccentric loading. The experimental axial capacities are compared to other established theoretical formulae on concentric loading to determine a possible relationship. The study found a good correlation between the reduction in axial capacity for different column lengths and hollow section ratios.

Keywords: CSDST, CFST, Axial Capacity.

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Authors: Ciceron Berbecaru, Marin Cernea, Gheorghe Virgil Aldica, Roxana Trusca

Abstract:

(Bi0.5Na0.5)TiO3 doped with 8 mol % BaTiO3 powder (BNT-BT0.08), prepared by sol-gel method was compacted and sintered by Spark Plasma Sintering (SPS) process. The influence of SPS temperature on the densification of BNT-BT0.08 ceramic was investigated. Starting from sol-gel nanopowder of BNT-BT containing 8 mol % BaTiO3 with an average particles size of about 30 nm, were obtained ceramics with density around 98 % of the theoretical density value when the SPS temperature used was about 850 °C. The average grain size of the resulting ceramics was 80 nm. The BNT-BT0.08 ceramic sample obtained by SPS method has shown good electric properties at various frequencies.

Keywords: (Bi0.5Na0.5)TiO3 doped with BaTiO3, Spark PlasmaSintering (SPS), dielectric properties

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Authors: M. Jouki, N. Khazaei , A. Kalbasi , H. Tavakolipour, S. Rajabifar, F. Motamedi. Sedeh, A. Jouki

Abstract:

Irradiation is considered one of the most efficient technological processes for the reduction of microorganisms in food. It can be used to improve the safety of food products, and to extend their shelf lives. The aim of this study was to evaluate the effects of gamma irradiation for improvement of saffron shelf life. Samples were treated with 0 (none irradiated), 1.0, 2.0, 3.0 and 4.0 kGy of gamma irradiation and held for 2 months. The control and irradiated samples were underwent microbial analysis, chemical characteristics and sensory evaluation at 30 days intervals. Microbial analysis indicated that irradiation had a significant effect (P < 0.05) on the reduction of microbial loads. There was no significant difference in sensory quality and chemical characteristics during storage in saffron.

Keywords: gamma irradiation, saffron, microbes, contamination.

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Authors: Chang Su Woo, Hyun Sung Park

Abstract:

Useful lifetime evaluation of chevron rubber spring was very important in design procedure to assure the safety and reliability. It is, therefore, necessary to establish a suitable criterion for the replacement period of chevron rubber spring. In this study, we performed characteristic analysis and useful lifetime prediction of chevron rubber spring. Rubber material coefficient was obtained by curve fittings of uniaxial tension equibiaxial tension and pure shear test. Computer simulation was executed to predict and evaluate the load capacity and stiffness for chevron rubber spring. In order to useful lifetime prediction of rubber material, we carried out the compression set with heat aging test in an oven at the temperature ranging from 50°C to 100°C during a period 180 days. By using the Arrhenius plot, several useful lifetime prediction equations for rubber material was proposed.

Keywords: Chevron rubber spring, material coefficient, finite element analysis, useful lifetime prediction.

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Authors: Smajo Bisanovic, Mensur Hajro, Mersiha Samardzic

Abstract:

This paper presents quantitative component criticality importance indices applicable for identifying and ranking critical components in the phase of thermal power plants design. Identifying critical components for power plant reliability provides one important input to decision-making and guidance throughout the development project. The study of components criticality importance indices to several characteristic structural schemes of conventional thermal power plant is presented and discussed.

Keywords: Component criticality importance measures, discrete event, reliability, thermal power plant.

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Authors: J. Cecrdle, J. Malecek

Abstract:

This paper deals with the conceptual design of the new aeroelastic demonstrator for the whirl flutter simulation. The paper gives a theoretical background of the whirl flutter phenomenon and describes the events of the whirl flutter occurrence in the aerospace practice. The second part is focused on the experimental research of the whirl flutter on aeroelastic similar models. Finally the concept of the new aeroelastic demonstrator is described. The demonstrator represents the wing and engine of the twin turboprop commuter aircraft including a driven propeller. It allows the changes of the main structural parameters influencing the whirl flutter stability characteristics. It is intended for the experimental investigation of the whirl flutter in the wind tunnel. The results will be utilized for validation of analytical methods and software tools.

Keywords: aeroelasticity, flutter, whirl flutter, W-WING demonstrator

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Authors: Changsoo Chon, Sangkuy Han, Donghyun Seo, Jihyung Park, Bokku Kang, Hansung Kim, Keyoungjin Chun, Cheolwoong Ko

Abstract:

The purpose of the study is to develop a finite element model based on 3D bone structural images of Micro-CT and to analyze the stress distribution for the osteoporosis mouse femora. In this study, results of finite element analysis show that the early osteoporosis of mouse model decreased a bone density in trabecular region; however, the bone density in cortical region increased.

Keywords: Micro-CT, finite element analysis, osteoporosis, bone strength.

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Authors: Ali Farhaninejad, Rizal Zahari, Ehsan Rasooliyazdi

Abstract:

Increasing energy absorption is a significant parameter in vehicle design. Absorbing more energy results in decreasing occupant damage. Limitation of the deflection in a side impact results in decreased energy absorption (SEA) and increased peak load (PL). Hence a high crash force jeopardizes passenger safety and vehicle integrity. The aims of this paper are to determine suitable dimensions and material of a square beam subjected to side impact, in order to maximize SEA and minimize PL. To achieve this novel goal, the geometric parameters of a square beam are optimized using the response surface method (RSM).multi-objective optimization is performed, and the optimum design for different response features is obtained.

Keywords: Crashworthiness, side impact, energy absorption, multi-objective optimization, Square beam, SEA

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